“…Values for ammonia in fresh milk obtained by methods of the first class fall in the range of 0.3 to 0.4 mg. per 100 cc. of milk, and the results are reasonably uniform (1,4,11,14,16,18). The results obtained by methods of the second class, using the Folin and Bell (7) Permutit adsorption principle, are decidedly different and more variable than those quoted above.…”